Electromagnetic card file



E. A. DAHL, JR

Aug. 1 i967 ELECTROMAGNETIC CARD FILE 2 Sheets-Sheet 1 Filed March 23,1966 QZW, MJ mm w M/w E. A. DAHL, JR

Aug. 1, 1967 ELECTROMAGNETIC v CARD FILE 2 Sheets-Sheet 2 Filed March23, 1966 United States Patent 3,333,591 ELECTROMAGNETIC CARD FILE ErnestA. Dahl, Jr., 729 Greenwood Ave., Wilmette, Ill. 60091 Filed Mar. 23,1966, Ser. N0. 536,762 6 Claims. (Cl. 12916) This invention relatesgenerally to card filing structure and more particularly to a cardfiling structure wherein magnetic repulsion is utilized to separate thefiling cards.

Magnetic repulsion is often used to separate file cards to facilitatelocating a desired card. It is a common practice, when magneticrepulsion is used to separate file cards, to mount a pair of magnets onopposite sides of the file structure as a source of a magnetic field.The magnetic field interacts with inserts of soft iron positionedbetween two layers of paper forming the card on which data is printed.The inserts of magnetic material in the file cards will be polarizedwith a similar polarity by the magnetic field. The similarly magnetizedinserts will establish repelling magnetic fields which will cause thecards to separate in the manner set forth in Patent No. 2,954,032 toErnest A. Dahl, Sr.

In using a magnetic card file, the cards are generally fanned orseparated to expose the data on the cards to visual scrutiny whilesearching for a particular card. After the desired file card has beenlocated, it is expedient to keep the file cards separated until theselected card is returned to its place in the file. However, the filingplace for a particular card is soon lost since magnetic repulsionbetween the various cards will cause the file to quickly spring back orreturn to normal as soon as the selected card is removed from the file.Thus, the user of the file structure will not be able, without searchingto determine the location from which a particular card has previouslybeen removed.

Another problem which arises when using a magnetic card file structureconcerns the filing of cards on which data is magnetically recorded. Themagnetically recorded data can be easily erased or altered by bringingthe file card within the influence of a magnetic field. When the filecard is removed from a magnetic card file structure, it is apparent thecard will pass through the field of the magnets mounted on oppositesides of the structure. The magnetic field will quickly alter themagnetically recorded data of the card.

Therefore, it is a main object of the present invention to provide amagnetic card filing structure which overcomes the aforementioneddisadvantages of prior art structures. Specifically, it is an object ofthis invention to provide a means for disabling the magnets of a cardfiling structure so that (1) cards having magnetically recorded data maybe filed in the structure and (2) the cards will remain open at a filinglocation from which a card has been removed.

Another object of this invention is to provide a magnetic card filingstructure with an interlock so that data cards can be removed from thefile only when the magnets have been disabled.

For a fuller understanding of the nature and objects of the inventionreference should be had to the following detailed description, taken inconnection with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a file card container embodying theinvention;

FIG. 2 is an enlarged detailed sectional view taken along the line 22showing the cross sectional structure of the file card container of FIG.1;

FIG. 3 is an enlarged detailed view of the interlock mechanism for thefile card container taken along the line 3-3 of FIG. 1;

FIG. 4 is an enlarged side view of the interlock mecha- 3,333,591Patented Aug. 1, 1967 nism and magnets taken along the line 4-4 of FIG.1;

FIG. 5 is a schematic drawing of a wiring diagram for the file cardstructure shown in FIG. 1; and

FIG. 6 is an enlarged, perspective view of an electromagnet utilized inthe file card structure of FIG. 1.

Considering first the broad structural aspects of a preferred embodimentof the invention, a card file container 10 is utilized to store filecards 12 upon which data has been magnetically recorded. The file cards12 have inserts 14 of a suitable magnetizable material, such as softiron. The file card container 10 includes electromagnets 16, 18, 20 and22 from which magnetic fields emanate to fan or separate the file cardsin the manner set forth in US. Patent 2,954,032. The electromagnets 16to 22 are energized by means of a control switch 24 which is mounted onthe side of the file container 10. The control switch 24 is normallyclosed to enable the magnets 16 to 22 to be energized. An interlock 26is provided to prevent the file cards from being removed from the filecontainer when the magnets are energized. When the interlock 26 is movedfrom the blocking position, shown in FIG. 2, to the release position,shown in FIG. 3, the control switch 24 is actuated to disable theelectromagnets. The disabled electromagnets will not alter or erase themagnetically recorded data on the card 12 as the card is removed fromthe container 10. Also the cards 12 will not be fanned or separated by amagnetic field emanating from the electromagnets so that the selectedfile card can be easily returned to its filing position.

Referring now to FIGS. 1 and 2 in greater detail, the card filestructure container 10 includes a pair of sloping end.walls 28 which areinterconnected by a pair of upwardly extending vertical sidewalls 30 and32. The end walls 28 and sidewalls 30 and 32 are interconnected by abase wall 34 upon which the lower edges of the file cards 12 rest. Theelectromagnets 16 to 22 are mounted in rectangular housings 36 and 38which are formed on an upper portion of the sidewalls 30 and 32. Thetops of the housings 36 and 38 are covered by a pair of flanges 40 and42 which are integrally formed with the sidewalls 30 and 32. The flanges40 and 42, as will be explained in greater detail subsequently, form amounting platform for the actuator assembly 26. Wires for theelectromagnets 16 to 22 are positioned in a transversely extending ductor housing 44 which is mounted along a front portion of the card filestructure 10. As will be seen from an inspection of FIG. 3, the wiringduct or housing 44 interconnects the two magnet housings 36 and 38.

Referring now to FIG. 4, the electromagnets 16 and 20 are connected tothe top of the housing 36 by screws 46. While only two of the magnets,magnets 16 and 20, have been shown in detail, it will be apparent thatthe magnets 18 and 22 are similar in both their construction andmounting. Magnets 16 and 20 are mounted adjacent to each other and havea combined length which extends for substantially the entire length ofthe file container 10. Since the magnets 18 and 22 are similarlymounted, a uniform magnetic field will be formed along the entire lengthof both sides of the file container 10 by the electromagnets 16 to 22.

Referring now to FIGS. 4 and 5, the electromagnets 16 to 22 includecoils 48, 50, 52 and 54 which are wound around the generally U-shapedcore pieces of the electromagnets. Coils 48 to 54 are connected to thecontrol switch 24 by wires 56. The wires 56 are connected to a suitablesource of electrical power, preferably volts A.C. current, by a cord 58having a connection plug 60. Since the switch 24 is normally closed thecoils 48 to 54 will be normally energized.

The energizing of the coils 48 to 54 also energizes a signal light 62 toinform the user that the card file structure is presently drawingelectrical power. As the electromagnets draw power, they will, due tothe electrical current in the coils 48 to 54, be heated. If the cardfile container is left plugged in for a long period of time, for exampleovernight, the electromagnets may overheat and cause a safety hazard.Therefore a suitable thermostatic switch 64 is provided to interrupt thecircuit when the temperature of the coils 48 to 54 exceeds apredetermined maximum value. The light 62 and thermostatic switch 64 areboth enclosed in a housing 66, see FIG. 3, which is connected to theflange 42 of the housing 38.

Referring now to FIGS. 2, 3 and 4-, the interlock 26 is mounted onbrackets 68 and 70 which are positioned at opposite end portions of thehousing 36. An interlock plate 72 is connected at opposite ends to thebrackets 68 and 70 by means of depending tabs or cars 74 and 76.Friction forces between the tabs 74 and 76 and the brackets 68 and 70normally retain the mounting plate in a horizontal blocking position asshown in FIG. 2. When the interlock plate 72 is in the horizontalblocking position, it will be positioned directly above an upper edge 78of the file cards 12. It is apparent from an inspection of FIG. 2 thatthe file cards 12 cannot be withdrawn from the file container since theinterlock plate 72 will engage the edge 78 of the cards to block theirupward movement.

A longitudinally extending actuator handle 80 is integrally formed withthe interlock plate 72. By depressing the handle 80 downwardly, as shownin FIG. 3, the interlock plate 72 is pivoted or rotated upwardly or awayfrom file cards 12 so that the file cards can be withdrawn from the filecontainer 10. Since the actuator handle 80 extends for the entire lengthof the interlock plate 72, a person using the card file structure 10 caneasily rotate the interlock plate to the release position shown in solidlines in FIG. 3 to remove a file card 12. The handle 80 includes anouter hook or lip 82 which extends for substantially the entire lengthof the handle and provides a surface against which the file cardstructure user may press to rotate the interlock plate back to theblocking position. As the interlock plate 72 is rotated back to theblocking position (indicated by dashed lines in FIG. 3), it will engagea stop member 84 which is positioned adjacent to the front of the filecontainer 10. When the bottom surface of the interlock plate 72 contactsan upper edge portion of the stop 84 the pivoting movement of theinterlock plate 72 will be terminated.

A depending foot or actuator lever 86 is connected to the lower surfaceof the interlock plate 72 at the forward end of the plate. The foot oractuating lever 84 contacts a pin 88 which is slidably mounted in theelectromagnet housing 36 to open the normally closed switch 24. When theinterlock 26 is moved from the blocking position, shown in FIG. 2, tothe release position shown in solid lines in FIG. 3, the foot or lever86 will contact the pin 88 to actuate the switch 24. When the switch 24is actuated, the coils 48 to 54 of the electromagnets will bedeenergized to disable the electromagnets 16 to 22. The disabling of theelectromagnets 16 to 22 will eliminate the magnetic field which had beenseparating the file cards 12.

For purposes of affording a more complete understanding of theinvention, it is advantageous now to provide a functional description ofthe mode in which the component parts thus far identified operate. Whenthe interlock 26 is pivoted to the blocking position, shown in FIG. 2,the interlock plate 72 will be positioned directly above the upper edge78 of the file cards so that they cannot be removed from the container10. With the interlock 26 in the blocking position, the switch 24 willbe closed and the electromagnets 16 and 22 will be energized. Magneticfields will then emanate from the energized electromagnets. Since theinserts 14 of magnetic material are magnetized by the fields emanatingfrom the electromagnets 16 to 24, the file cards 12 will be fanned orseparated. If a file card 12 were to be withdrawn from a file container10, while the electromagnets 16 to 22 are energized, the filing positionfrom which the card was wit-hdrawn would be quickly lost since theadjacent cards would fan into the filing place under the influence ofthe repelling magnetic inserts 14. Also, the magnetically recorded dataon the file cards 12 would be erased or altered, by the magnetic fieldsemanating from the electromagnets 16 to 22, as the card was removed.However, the interlock 26 prevents the file cards 12 from beingwithdrawn from the file container 10 when the electromagnets areenergized.

When a file card is to be removed from a file container 10, theinterlock handle is depresed to pivot the interlock to the releaseposition, shown in solid lines in FIG. 3. As the interlock 26 is rotatedto the release position, the depending lever or foot 86 will depresssliding pin 88 to actuate the switch 24 to the open position to disablethe electromagnets 16 to 24. When the electromagnets 16 to 24 aredisabled, the file card 12 may be removed from the file container 10without altering any magnetic data which is recorded on the card 12.

Since the electromagnets 16 to 22 were disabled as the card was removedfrom the file container, the cards 12 remaining in the file containerwill lay open to mark the filing position from which the selected cardwas removed. Thus the refiling of the selected card will be greatlyfacilitate since the file will remain open to indicate its filingposition. After the card has been inserted into the container, the sidehook or lip 82 of the actuator handle 89 is grasped to swing theinterlock to the blocking position. As the interlock place 72 swingsdownwardly to the blocking position, it will be engaged by an upper edgeof the stop 84 to terminate the pivoting movement when the interlockplate 72 is substantially horizontal. As the interlock plate 72 is swungto the blocking position, the foot or lever 86 will release the pin 88so that the switch will again close to energize the electromagnets 16 to22. Since the magnets have been energized, the magnetic file cards 12will be fanned or separated to facilitate the location of another filecard.

The construction of the electromagnets 16 to 22 is similar to that ofthe electromagnet shown in FIG. 6. The electromagnets are fabricatedwith a core 90 which has a pair of substantially parallel side members92 and 94. The side members 92 and 94 are interconnected by a basemember 96 around which a coil 98, similar to the coils 48 to 54, iswound. The electromagnet has a length 100 which is considerably greaterthan the width 102 of the magnet. Since the length is greater than thewidth, there will be formed a magnetic field which will flow from oneside member 94 to the other side member 92. This magnetic field will besubstantially uniform over the entire length of the electromagnet sothat all of the file cards 12 will be subjected to a relatively uniformfield. It will be apparent that if the width is greater than the lengththe magnetic field would not be uniform due to variations in themagnetic field at the relatively close ends of the magnet.

While two electromagnets have been utilized on each side of the cardfile structure 10, it will be apparent to those skilled in the art thata single long electromagnet could equally as well be used. In apreferred embodiment two electromagnets are utilized since it has beenfound that the heating and hysteresis losses with two magnets of arelatively short length is less than the losses which are incurred witha single long magnet. In the preferred embodiment slots or apertures 104are provided in the side members 92 and 94 of the core piece 90. Theslots 104 break up the hysteresis currents which are set up in the coreand tend to reduce the hysteresis losses when the magnets are energized.

While particular embodiments of the invention have been shown, it shouldbe understood, of course, that the invention is not limited theretosince many modifications may be made; and it is, therefore, contemplatedto cover by the appended claims any such modifications that fall withinthe true spirit and scope of the invention.

What is claimed is:

1. A card file structure including a file container having first andsecond spaced apart sidewalls, first magnet means mounted adjacent tosaid first sidewall, second magnet means mounted adjacent to said secondsidewall, file card means juxtaposed in said container intermediate saidfirst and second magnet means, said file card means adapted to containmagnetically recorded data, said file card means having portions of amagnetizable material positioned adjacent said first and second magnetmeans, magnet control means mounted on said file container for movementfrom a first neutral position wherein said portions of magnetizablematerial are magnetized by magnetic fields emanating from said first andsecond magnet means to a second disabling position wherein said portionsof magnetizable material are free from the influence of the magneticfields of said first and second magnet means, said control means in saidsecond position eliminating the magnetic field from said first andsecond magnetic means from between said first and second sidewalls ofsaid file container to prevent altering of magnetic data on said filecard means while said file card means are being withdrawn from thecontainer, interlock means mounted on said file container for movementfrom a first position blocking the removal of said file card means fromsaid file container to a second release position enabling said file cardmeans to be removed from said file card container, and actuator meansmounted on said file container, said actuator means interconnecting saidcontrol means and interlock means to move said control means from saidfirst neutral position to said second disabling position when saidinterlock means is moved from said first blocking position to saidsecond release position, whereby said file card means can only beremoved from said file container when the magnetic fields from saidfirst and second magnet means have been disabled.

2. A card file structure including a file container having first andsecond spaced apart sidewalls, first electromagnet means mountedadjacent to said first sidewall, second electromagnet means mountedadjacent to said second sidewall, file card means juxtaposed in saidcontainer intermediate said first and second electromagnet means, saidfile card means having portions of a magnetizable material positionedadjacent said first and second electromagnet means, magnet control meansmounted on said file container for moving from a first neutral positionwherein said portions of magnetizable material are magnetized bymagnetic fields emanating from said first and second electromagnet meansto a second disabling position wherein said portions of magnetizablematerial are free from the influence of the magnetic fields of saidfirst and second electromagnet means, said control means includingcircuit means for connecting said electromagnets to a source ofelectrical power and switch means for interrupting said circuit means todisconnect said electromagnets from said source of power when saidcontrol means is in said second disabling position, interlock meansmounted on said file container for movement from a first positionblocking the removal of said file card means from said file container toa second release position enabling said file card means to be removedfrom said file card container, and actuator means mounted on said filecontainer, said actuator means interconnecting said control means andinterlock means to move said control means from said first neutralposition to said second disabling position when said interlock means ismoved from said first blocking position to said second release position,whereby said file car-d means can only be removed from said filecontainer when the magnetic fields from said first and secondelectromagnet means have been disabled.

3. A card file structure as set forth in claim 2 wherein; said circuitmeans includes signal means to indicate when said electromagnets areenergized by the source of electrical power, and thermal electric switchmeans to disconnect said electromagnets from said source of power whenthe temperature of said electromagnets exceeds a predetermined amount.

4. A card file structure as set forth in claim 2 wherein; said firstmagnet means includes a plurality of adjacent electromagnets and saidsecond magnet means includes a plurality of adjacent electromagnets.

5. A card file structure including a file container having first andsecond spaced apart sidewalls, first magnet means mounted adjacent tosaid first sidewall, second magnet means mounted adjacent to said secondsidewall, file card means juxtaposed in said container intermediate saidfirst and second magnet means, said file card means having portions of amagnetizable material positioned adjacent said first and second magnetmeans, magnet control means mounted on said file container for movementfrom a first neutral position wherein said portions of magnetizablematerial are magnetized by magnetic fields emanating from said first andsecond magnet means to a second disabling position wherein said portionsof magnetizable material are free from the influence of the magneticfields of said first and second magnet means, interlock means mounted onsaid file container for movement from a first position blocking theremoval of said file card means from said file container to a secondrelease position enabling said file card means to be removed from saidfile card container, said interlock means includes an interlock plateextending for substantially the entire length of said file container,said plate being located in a generally horizontal position adjacent toan uppermost edge portion of said file card means when said interlockmeans is in said first blocking position to prevent the removal of afile card from said container, and actuator means mounted on said filecontainer, said actuator means interconnecting said control means andinterlock means to move said control means from said first neutralposition to said second disabling position when said interlock means ismoved from said first blocking position to said second release position,whereby said file card means can only be removed from said filecontainer when the magnetic fields from said first and second magnetmeans have been disabled.

6. A card file structure as set forth in claim 5 wherein; said interlockmeans further includes mounting bracket means connected to said filecontainer to pivotably mount said interlock plate for movement from saidfirst blocking position to said second release position, stop meanssupported by said file container for limiting the pivoting movement ofsaid interlock plate when said plate is in said first blocking positionto prevent said plate from pivoting into contact with said file cardmeans, and protruding handle means connected to said interlock plate tofacilitate the pivoting of said plate from said first blocking positionto said second release position.

References Cited UNITED STATES PATENTS 2,341,639 2/1944 Mathiesen 129162,495,490 1/1950 Whitson 12916.1 2,698,212 12/ 1954 Sevebeck l29l6 X2,722,936 11/1955 Mathiesen 129-16 2,984,243 5/ 1961 Mathiesen 129-163,073,313 1/1963 Mittag 12.9-16.1

JEROME SCHNALL, Primary Examiner.

1. A CARD FILE STRUCTURE INCLUDING A FILE CONTAINER HAVING FIRST ANDSECOND SPACED APART SIDEWALLS, FIRST MAGNET MEANS MOUNTED ADJACENT TOSAID FIRST SIDEWALL, SECOND MAGNET MEANS MOUNTED ADJACENT TO SAID SECONDSIDEWALL, FILE CARD MEANS JUXTAPOSED IN SAID CONTAINER INTERMEDIATE SAIDFIRST AND SECOND MAGNET MEANS, SAID FILE CARD MEANS ADAPTED TO CONTAINMAGNETICALLY RECORDED DATA, SAID FILE CARD MEANS HAVING PORTIONS OF AMAGNETIZABLE MATERIAL POSITIONED ADJACENT SAID FIRST AND SECOND MAGNETMEANS, MAGNET CONTROL MEANS MOUNTED ON SAID FILE CONTAINER FOR MOVEMENTFROM A FIRST NEUTRAL POSITION WHEREIN SAID PORTIONS OF MAGNETIZABLEMATERIAL ARE MAGNETIZED BY MAGNETIC FIELDS EMANATING FROM SAID FIRST ANDSECOND MAGNET MEANS TO A SECOND DISABLING POSITION WHEREIN SAID PORTIONSOF MAGNETIZABLE MATERIAL ARE FREE FROM THE INFLUENCE OF THE MAGNETICFIELDS OF SAID FIRST AND SECOND MAGNET MEANS, SAID CONTROL MEANS IN SAIDSECOND POSITION ELIMINATING THE MAGNETIC FIELD FROM SAID FIRST ANDSECOND MAGNETIC MEANS FROM BETWEEN SAID FIRST AND SECOND SIDEWALLS OFSAID FILE CONTAINER TO PREVENT ALTERING OF MAGNETIC DATA ON SAID FILECARD MEANS WHILE SAID FILE CARD MEANS ARE BEING WITHDRAWN FROM THECONTAINER, INTERLOCK MEANS MOUNTED ON SAID FILE CONTAINER FOR MOVEMENTFROM A FIRST POSITION BLOCKING THE REMOVAL OF SAID FILE CARD MEANS FROMSAID FILE CONTAINER TO A SECOND RELEASE POSITION ENABLING SAID FILE CARDMEANS TO BE REMOVED FROM SAID FILE CARD CONTAINER, AND ACTUATOR MEANSMOUNTED IN SAID FILE CONTAINER, SAID ACTUATOR MEANS INTERCONNECTING SAIDCONTROL MEANS AND INTERLOCK MEANS TO MOVE SAID CONTROL MEANS FROM SAIDFIRST NEUTRAL POSITION TO SAID SECOND DISABLING POSITION WHEN SAIDINTERLOCK MEANS IS MOVED FROM SAID FIRST BLOCKING POSITION TO SAIDSECOND RELEASE POSITION, WHEREBY SAID FILE CARD MEANS CAN ONLY BEREMOVED FROM SAID FILE CONTAINER WHEN THE MAGNETIC FIELDS FROM SAIDFIRST AND SECOND MAGNET MEANS HAVE BEEN DISABLED.